TDChip Posted December 11, 2023 Share Posted December 11, 2023 I’m trying to get my father’s old Gen 5 up and running. He parked it in the garage 5 years ago and hadn’t touched it since. I replaced the battery immediately so assume all of these tests were done with a fully charged battery. All fuses were in good condition. The first thing I did was remove the PAIR system because it was so hard to work around. I found that the residual gas left in the tank rusted the internal fuel pump/filter and some of the tank. So I cleaned that out, resealed it, replaced the fuel pump with an after market QFS oem replacement. When the fuel pump still wouldn’t prime I traced the problem to the fuel shutoff relay. I ordered a replacement on Amazon (which turned out to not be the model I ordered) so while I wait for the new OEM one to come, I bypassed the relay which now allows the fuel pump to prime. The problem is it doesn’t stop priming. Is this related to the fuel shutoff relay or is it a pressure sensor? Any thoughts? Even with the fuel pump going, I cannot get the engine to start. Spark plugs look fine, engine is turning over. Oxygen is fine. The next thing I’m going to do will be to disassemble and clean the fuel injection assembly. And hopefully it is just clogged injectors. Any help would be appreciated, especially around the relays - I’m used to working on track bikes, I’m not used to all of the sensors and relays on this bike. IMG_0052.mov Quote Link to comment Share on other sites More sharing options...
Member Contributer Grum Posted December 11, 2023 Member Contributer Share Posted December 11, 2023 1 hour ago, TDChip said: I found that the residual gas left in the tank rusted the internal fuel pump/filter and some of the tank. So I cleaned that out, resealed it, replaced the fuel pump with an after market QFS oem replacement. When the fuel pump still wouldn’t prime I traced the problem to the fuel shutoff relay. I ordered a replacement on Amazon (which turned out to not be the model I ordered) so while I wait for the new OEM one to come, I bypassed the relay which now allows the fuel pump to prime. The problem is it doesn’t stop priming. Is this related to the fuel shutoff relay or is it a pressure sensor? Any thoughts? If you've bypassed the Fuel Cut Relay to get your pump running then that is the reason the pump doesn't stop after Ignition Switch On! The ECM controls the Fuel Cut Relay coil Ground side, with it bypassed this cannot happen. BE EXTREMELY CAREFUL IN BYPASSING THE FCR, GET IT WRONG AND YOU'LL DESTROY YOUR ECM! You only need to jumper one of the Black/White wires to the Brown wire NOT the Brown/Black ECM wire. Unfortunately, looking at your photo it appears like you may have done just that, jumpered 12v to the Brown/Black ECM Ground output for the FCR.!!!!! There should ONLY be one jumper wire. See Attached photo - The guy that did this destroyed his ECM, does the jumpering look familiar? No the relay socket hasn't melted, its just drowned in Dielectric Grease! For Info - You can always use say the Hi Beam Relay in the Fuel Cut Relay position as Hi Beam, Lo Beam, Fuel Cut and Engine Stop Relays are the same type. Quote Link to comment Share on other sites More sharing options...
TDChip Posted December 11, 2023 Author Share Posted December 11, 2023 3 hours ago, Grum said: If you've bypassed the Fuel Cut Relay to get your pump running then that is the reason the pump doesn't stop after Ignition Switch On! The ECM controls the Fuel Cut Relay coil Ground side, with it bypassed this cannot happen. BE EXTREMELY CAREFUL IN BYPASSING THE FCR, GET IT WRONG AND YOU'LL DESTROY YOUR ECM! You only need to jumper one of the Black/White wires to the Brown wire NOT the Brown/Black ECM wire. Unfortunately, looking at your photo it appears like you may have done just that, jumpered 12v to the Brown/Black ECM Ground output for the FCR.!!!!! There should ONLY be one jumper wire. See Attached photo - The guy that did this destroyed his ECM, does the jumpering look familiar? No the relay socket hasn't melted, its just drowned in Dielectric Grease! For Info - You can always use say the Hi Beam Relay in the Fuel Cut Relay position as Hi Beam, Lo Beam, Fuel Cut and Engine Stop Relays are the same type. Thanks for the warning and info that the headlight relay is the same. I’ll pull that and swap until the oem arrives. Quote Link to comment Share on other sites More sharing options...
TDChip Posted December 11, 2023 Author Share Posted December 11, 2023 18 hours ago, Grum said: BE EXTREMELY CAREFUL IN BYPASSING THE FCR, GET IT WRONG AND YOU'LL DESTROY YOUR ECM! Unfortunately, looking at your photo it appears like you may have done just that, jumpered 12v to the Brown/Black ECM Ground output for the FCR.!!!!! Hey Grum, what should I look for to check that I did/didn’t burn out the ECM doing this? Quote Link to comment Share on other sites More sharing options...
Member Contributer Grum Posted December 12, 2023 Member Contributer Share Posted December 12, 2023 7 hours ago, TDChip said: Hey Grum, what should I look for to check that I did/didn’t burn out the ECM doing this? Sadly (damn shame actually), you should have closely looked at the wiring diagram for your bike as well as having a bit of a read of the Service Manual (downloadable from this forum) before doing what you did! Section 5 of the Service Manual, Fuel Flow Test actually shows you how to bypass the FCR. To just simply jumper wires that you had no understanding of is a fatal mistake! By placing +12v on the Ground (Brown/Black wire) from the ECM to control the FCR will have blown the internal switching for Fuel Pump control - rendering your ECM useless. You created a Dead Short +12v to Ground, passing through the ECM, either Sub Fuse B 20amp would have Blown OR the ECM blown open circuit, the ECM is by far the weakest link in this situation! You will have no fuel prime or fuel pump operation controlled from the ECM, who knows what other internal damage may have been done. You might have the Fi Light (MIL) permanetly On meaning serious issues with the ECM. To answer your previous question - The ECM receives no direct feedback from the fuel pressure regulator. At switch On, the ECM provides a Ground for the FCR Coil to energise it and run the Fuel Pump for approx 2 to 3 secs then turns OFF. Once the engine is cranked over for starting and the ECM receives Crank Pulses it will again energise the FCR to run the Fuel Pump. Good luck with the bike and sourcing a replacement ECM! Quote Link to comment Share on other sites More sharing options...
Member Contributer Duc2V4 Posted December 12, 2023 Member Contributer Share Posted December 12, 2023 Snap a pic of the ECM sticker showing the numbers, I may be able to provide you a replacement for you. Cheers, D 1 Quote Link to comment Share on other sites More sharing options...
TDChip Posted December 12, 2023 Author Share Posted December 12, 2023 10 hours ago, Duc2V4 said: Snap a pic of the ECM sticker showing the numbers, I may be able to provide you a replacement for you. Cheers, D @Grum thanks man. Seems like I got myself into a mess here. I was expecting there to be a burnt contact or funny FI code, but alas :’( The FI codes are flashing (19) for pulse ignition system fault - but that is probably because I have removed the injectors to clean them. @Duc2V4 if you’ve got one I can buy off of you, I’d be very appreciative. Can’t buy this stuff off eBay with any reliability. Attached is the pic. Quote Link to comment Share on other sites More sharing options...
Member Contributer Duc2V4 Posted December 12, 2023 Member Contributer Share Posted December 12, 2023 I'll check what I have and message you if I have a matching unit. Cheers, D Quote Link to comment Share on other sites More sharing options...
Member Contributer Grum Posted December 12, 2023 Member Contributer Share Posted December 12, 2023 3 hours ago, TDChip said: The FI codes are flashing (19) for pulse ignition system fault - but that is probably because I have removed the injectors to clean them ???? Is that how you interpret a code 19? You're "probably" just guessing I guess.!! Quote Link to comment Share on other sites More sharing options...
TDChip Posted December 12, 2023 Author Share Posted December 12, 2023 2 hours ago, Grum said: ???? Is that how you interpret a code 19? You're "probably" just guessing I guess.!! I obviously defer to your experience. I’ve been working on VFRs for a total of 1 week. But that’s what code 19 says so I’m working through its troubleshooting procedures. Quote Link to comment Share on other sites More sharing options...
Member Contributer Grum Posted December 12, 2023 Member Contributer Share Posted December 12, 2023 5 hours ago, Grum said: The FI codes are flashing (19) for pulse ignition system fault - but that is probably because I have removed the injectors to clean them 3 hours ago, TDChip said: I obviously defer to your experience. I’ve been working on VFRs for a total of 1 week. But that’s what code 19 says so I’m working through its troubleshooting procedures. You assumed you knew how to bypass the FCR, then wonder why the Fuel Pump continues to run! Now you're assuming your code 19 is because you've removed the injectors. Why no Injector codes then? Code 19 is an Ignition Pulse Generator Fault! Not a Fuel Injector Fault or "pulse ignition system fault". - Don't assume or guess things, use the wiring diagram and the Service Manual. A Digital Multi Meter is your best electrical tool, it's knowing how to use it that counts. Best to recheck when you have a replacement ECM fitted. As mentioned, who knows what damage is done to the ECM internals, it could be sending erroneous fault codes for various systems. Quote Link to comment Share on other sites More sharing options...
TDChip Posted December 12, 2023 Author Share Posted December 12, 2023 Well, I had removed the whole ignition system including the pulse generator, but that’s also why I’m looking for this group’s insights. Cheers. Quote Link to comment Share on other sites More sharing options...
Member Contributer Grum Posted December 13, 2023 Member Contributer Share Posted December 13, 2023 1 hour ago, TDChip said: Well, I had removed the whole ignition system including the pulse generator, but that’s also why I’m looking for this group’s insights. Cheers. You didn't mention this, how are we supposed to know? I won't ask why you removed the whole Ignition System. In order to help you with your situation proper details of what you've done to save us guessing will help a lot. A classic example of poor electrical fault finding are statements like, Fuses look good, I''m guessing its this or that, Grounds look good, etc. Measure voltages or continuity to confirm statements like this. Getting back to your FCR bypassing - If you'd only taken a short time to understand how a simple relay works and a quick look at the wiring diagram you would have realised ONLY the relay main contacts of the Relay connector (Black/White wire to the Brown Fuel Pump wire) needed to be shorted to continuously run the Fuel Pump. Then if you looked at how the relay coil is controlled you would have noticed the constant 12v from the ESR and another wire going to the ECM which has to be a Ground. A word of advice regarding Honda's wiring - A Black wire does NOT always mean its a Negative, nor does a Red mean it's always Positive. Examples...... - The all important Black/White wire on the ESR, FCR, ECM etc is the main +12v for ALL your EFI stuff. - The Black wire from your Kill Switch to the ESR coil is +12v - The other side of the ESR coil is Red/Orange wire, this is Negative/Ground, controlled by the BAS (Bank Angle Sensor). Seriously......Be very careful with whatever you do regarding your bikes electrical system, assuming and guessing is not an option as you've just discovered. Costly, time wasting, and further complications can easily be introduced. If you are not competent with the electrics, you really need to find someone who is. The 5th gen can have some tricky Ground issues, and once your engine is running, a thorough check of the charging system should be done. Once these issue are checked and sorted the 5th gen is a fantastc bike, especially the Yellow ones!. Oh yes, and don't forget the other maintenance issues, especially flushing the old coolant, brake and clutch fluids, etc. Again, Best of Luck with the bike. Quote Link to comment Share on other sites More sharing options...
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